Possible typo in AFLplusplus configuration

Hi,

I checked [AFLplusplus's description](https://github.com/google/fuzzbench/blob/master/fuzzers/aflplusplus/description.md) and [fuzzer.py](https://github.com/google/fuzzbench/blob/master/fuzzers/aflplusplus/fuzzer.py), and noticed a possible mismatch.

The description says it uses the `fast` power schedule, but I couldn't find anywhere in the [fuzzer.py](https://github.com/google/fuzzbench/blob/master/fuzzers/aflplusplus/fuzzer.py) that it is enabled.

I just wanted to ask whether this is a typo or where it is set.

Best,
Manuel